77 lines
3.0 KiB
Python
77 lines
3.0 KiB
Python
from pymodbus.client.tcp import ModbusTcpClient
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from pymodbus.exceptions import ModbusException
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import struct
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def read_register_float_value(host: str, port: int, address: list[int]):
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"""
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从modbus 读取数据
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:param port: 端口
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:param host: 地址
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:param address: 减去40000的偏移量
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:return: float值
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"""
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result_dict = {}
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client = ModbusTcpClient(host=host, port=port)
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try:
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# 连接到 Modbus 设备
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if client.connect():
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for add in address:
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# 从起始地址为 40002 的寄存器读取数据（Modbus 地址从 0 开始，所以 40003 对应 40002）
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result = client.read_holding_registers(address=add, count=2) # 读取 2 个寄存器，因为一个 float 占用 2 个寄存器
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if not result.isError():
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# 获取寄存器值列表
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register_values = result.registers
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# 将寄存器值转换为字节表示
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packed_bytes = bytes()
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for value in register_values:
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packed_bytes += value.to_bytes(2, byteorder='big')
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# 将字节表示转换为浮点数
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float_value = struct.unpack('>f', packed_bytes)[0] # 使用大端序
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result_dict[add] = float_value
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else:
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print("读取数据失败：", result)
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return False, None
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return True, result_dict
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else:
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print("无法连接到 Modbus 设备")
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return False, None
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except ModbusException as e:
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print("发生 Modbus 异常:", e)
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return False, None
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finally:
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# 关闭连接
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client.close()
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def write_register(host: str, port: int, address: int, value):
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"""
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写数据
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:param host: 地址
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:param port: 端口
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:param address: 地址
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:param value: 值
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:return:
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"""
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client = ModbusTcpClient(host=host, port=port)
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try:
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# 连接到 Modbus 设备
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if client.connect():
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# 将浮点数转换为字节表示
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packed_float = struct.pack('>f', value)
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# 将字节转换为 16 位整数列表，因为每个寄存器是 16 位
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registers = [int.from_bytes(packed_float[i:i + 2], byteorder='big', signed=False) for i in
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range(0, len(packed_float), 2)]
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# 向起始地址为 40000 的寄存器写入数据（Modbus 地址从 0 开始，所以 40001 对应 40000）
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result = client.write_registers(address=address, values=registers)
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if not result.isError():
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return True, "浮点数写入成功"
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else:
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return False, "浮点数写入失败:" + result
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else:
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return False, "无法连接到 Modbus 设备"
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except ModbusException as e:
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return False, "发生 Modbus 异常:" + e
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finally:
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# 关闭连接
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client.close() |